Smart wrist devices such as the Apple Watch are still a relatively small piece of the wearables market today, but that's set to change in a big way over the next few years.

So predicts market researcher IDC, which on Monday published a new report suggesting that there's explosive growth in store for the wearables market, driven largely by an expanding list of smartwatch vendors, devices, experiences and price points.

"We are at a stage now where more vendors are getting into this segment, setting the stage for more selection and ultimately more volumes," said Ramon Llamas, IDC's research manager for wearables. "Potential buyers wary of what is currently available will most likely be more interested once the second- and third-generation devices come to market with improved hardware and applications."

Wearable device shipments overall will reach more than 76 million units this year, up a whopping 164 percent from the 29 million units shipped in 2014, according to IDC's Worldwide Quarterly Wearable Device Tracker. By 2019, worldwide shipments will surpass 173 million units, the researcher predicts, for a five-year compound annual growth rate of almost 23 percent.

It's really smart wearables -- as opposed to what IDC calls "basic" ones such as fitness trackers -- where things get interesting, though.

Smart devices currently account for only about a third of the total market, but that's expected to change in 2018.

"Smart wearables will quickly move from a smartphone accessory primarily focused on notifications to a more advanced wearable computer capable of doing more processing on its own," said Jitesh Ubrani, senior research analyst for IDC's Mobile Device Trackers.

Driving the category is smart wristwear capable of running third-party applications. That includes not just the Apple Watch but also Motorola's Moto 360, Samsung's Gear S-series and Pebble's Time, for example.

Looking ahead, devices will increasingly be differentiated by the operating systems that run them as well as the available applications, IDC said.

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Katherine Noyes has been an ardent geek ever since she first conquered Pyramid of Doom on an ancient TRS-80. Today she covers enterprise software in all its forms, with an emphasis on cloud computing, big data, analytics and artificial intelligence.